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Partager le résultat de cette recherche Interroger des sources externesEtude de l'effet de la polarité des dislocations et de l'hydrogène sur les propriétés électriques et optiques de n-Cd et p-Cdo.96 Zn0.04 Te / Nouredine Brihi
Titre : Etude de l'effet de la polarité des dislocations et de l'hydrogène sur les propriétés électriques et optiques de n-Cd et p-Cdo.96 Zn0.04 Te Type de document : texte imprimé Auteurs : Nouredine Brihi ; Univ. de Constantine, Éditeur scientifique ; K. Guergouri, Directeur de thèse Année de publication : 2000 Importance : 157 f. Format : 30 cm Note générale : 01 Disponible dans la salle de recherche
02 Disponibles au magasin de la bibliothèque centraleLangues : Français (fre) Catégories : Français - Anglais
PhysiqueTags : Hydrogénation Dislocations CdTe et CdZnTe Micro indentation Rosette d'indentation Luminescence Index. décimale : 530 Physique Permalink : index.php?lvl=notice_display&id=3052 Etude de l'effet de la polarité des dislocations et de l'hydrogène sur les propriétés électriques et optiques de n-Cd et p-Cdo.96 Zn0.04 Te [texte imprimé] / Nouredine Brihi ; Univ. de Constantine, Éditeur scientifique ; K. Guergouri, Directeur de thèse . - 2000 . - 157 f. ; 30 cm.
01 Disponible dans la salle de recherche
02 Disponibles au magasin de la bibliothèque centrale
Langues : Français (fre)
Catégories : Français - Anglais
PhysiqueTags : Hydrogénation Dislocations CdTe et CdZnTe Micro indentation Rosette d'indentation Luminescence Index. décimale : 530 Physique Permalink : index.php?lvl=notice_display&id=3052 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité BRI/3415 BRI/3415 Thèse Bibliothèque principale Thèses Disponible
Titre : Interaction élastique dislocations- joints de grains dans les matériaux anisotropes de structure hexagonale (Be, Ti, Tl, Co, Hf, Y, Mg, Zr, Cd, Zn) Type de document : texte imprimé Auteurs : Mahdia Toubane -Siah ; Univ. de Constantine, Éditeur scientifique ; Omar Khalfallah, Directeur de thèse Année de publication : 2004 Importance : 124 f. Note générale : 01 Disponible à la salle de recherche
02 Disponibles au magasin de la bibliothèque centraleLangues : Français (fre) Catégories : Français - Anglais
PhysiqueTags : Anisotropie Dislocations Interaction élastique Force image Structure Hexagonale Joints de grains Index. décimale : 530 Physique Permalink : index.php?lvl=notice_display&id=3011 Interaction élastique dislocations- joints de grains dans les matériaux anisotropes de structure hexagonale (Be, Ti, Tl, Co, Hf, Y, Mg, Zr, Cd, Zn) [texte imprimé] / Mahdia Toubane -Siah ; Univ. de Constantine, Éditeur scientifique ; Omar Khalfallah, Directeur de thèse . - 2004 . - 124 f.
01 Disponible à la salle de recherche
02 Disponibles au magasin de la bibliothèque centrale
Langues : Français (fre)
Catégories : Français - Anglais
PhysiqueTags : Anisotropie Dislocations Interaction élastique Force image Structure Hexagonale Joints de grains Index. décimale : 530 Physique Permalink : index.php?lvl=notice_display&id=3011 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité TOU/4051 TOU/4051 Thèse Bibliothèque principale Thèses Disponible
Titre : Interaction dislocation – joints de grains dans l’Alumine Alpha. Type de document : texte imprimé Auteurs : Sherazed Moulahem, Auteur ; Omar Khalfallah, Directeur de thèse Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2019 Importance : 222 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Catégories : Français - Anglais
PhysiqueTags : sciences des matériaux : métallurgie Alumine Alpha Bicristaux Force image Déformation Dislocation Joint de grains Mécanismes d’accommodation Microscopie électronique en
transmission Alumina-Alpha Bicristals Image Force Deformation Grain Boundaries Dislocations Accommodation Mechanisms Transmission Electron Microscopy دود حبيبات المادة انخلا عات قوة الصورة المجهر الالكتروني النافد أكسيد
ألمنيوم الفا ثنائيات تشويه الإنخلاعات ميكانيزمات التكييفIndex. décimale : 530 Physique Résumé : The interaction between matrix dislocations and grain boundaries is at the origin of many mechanical properties of polycrystals. Two types of stress transfer processes may occur: slip transmission and matrix dislocation accommodation in boundaries with diffusion. The accommodation mechanisms depend on intergranular structure and dopants. Our investigations done on the alumina-alpha bicrystals, which are in: the rhombohedral twin orientation and Y or Mg doped, and the twin orientation with (011 ̅5) boundary plane and La doped or undoped. The purpose of this study is to calculate the image force due to dislocationgrain boundary interaction and to determine the accommodation process of matrix dislocation during a creep, the deformation conditions (Temperature, Stress, Orientations,) are determined so as to activate two basal slip systems in each grain. * The elastic interaction energy between dislocation and grain boundary is calculated on the basis of the theory of the elasticity in anisotropic materials, and the image force is deduced. The interaction energies determined are represented by the draw iso-energy maps, the maps present no symmetry , the maximal extreme values of the image force is noted for Burgers vector Diplôme : Doctorat en sciences En ligne : ../theses/physique/MOU7486.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=11318 Interaction dislocation – joints de grains dans l’Alumine Alpha. [texte imprimé] / Sherazed Moulahem, Auteur ; Omar Khalfallah, Directeur de thèse . - جامعة الإخوة منتوري قسنطينة, 2019 . - 222 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
PhysiqueTags : sciences des matériaux : métallurgie Alumine Alpha Bicristaux Force image Déformation Dislocation Joint de grains Mécanismes d’accommodation Microscopie électronique en
transmission Alumina-Alpha Bicristals Image Force Deformation Grain Boundaries Dislocations Accommodation Mechanisms Transmission Electron Microscopy دود حبيبات المادة انخلا عات قوة الصورة المجهر الالكتروني النافد أكسيد
ألمنيوم الفا ثنائيات تشويه الإنخلاعات ميكانيزمات التكييفIndex. décimale : 530 Physique Résumé : The interaction between matrix dislocations and grain boundaries is at the origin of many mechanical properties of polycrystals. Two types of stress transfer processes may occur: slip transmission and matrix dislocation accommodation in boundaries with diffusion. The accommodation mechanisms depend on intergranular structure and dopants. Our investigations done on the alumina-alpha bicrystals, which are in: the rhombohedral twin orientation and Y or Mg doped, and the twin orientation with (011 ̅5) boundary plane and La doped or undoped. The purpose of this study is to calculate the image force due to dislocationgrain boundary interaction and to determine the accommodation process of matrix dislocation during a creep, the deformation conditions (Temperature, Stress, Orientations,) are determined so as to activate two basal slip systems in each grain. * The elastic interaction energy between dislocation and grain boundary is calculated on the basis of the theory of the elasticity in anisotropic materials, and the image force is deduced. The interaction energies determined are represented by the draw iso-energy maps, the maps present no symmetry , the maximal extreme values of the image force is noted for Burgers vector Diplôme : Doctorat en sciences En ligne : ../theses/physique/MOU7486.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=11318 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité MOU/7486 MOU/7486 Thèse Bibliothèque principale Thèses Disponible 
Titre : Interaction elastique dislocation-interface dans des aux bicristaux elastiquement anisotropes de structure hexagonale Type de document : texte imprimé Auteurs : Aicha Ayadi, Auteur ; Omar Khalfallah, Directeur de thèse Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2015 Importance : 167 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Catégories : Français - Anglais
PhysiqueTags : Interface Dislocation Force image Contrainte de Peierls système de glissement structure
hexagonale élasticité anisotrope Dislocations Image Force Peierls stress slip system hexagonal structure elastic anisotropy
إنخلاع مستوى الانزلاق بنية سداسية قوة الصورة طاقة التفاعل المرن إجهاد Peierls تباين الخواص المرونيةIndex. décimale : 530 Physique Résumé : The movement of a dislocation in interaction with an interface, in the absence of external
stresses, is controlled by the balance of internal stresses. This assessment includes the friction force in the Peierls-Nabarro network stress and a force due to the anisotropy of the material called image force. We study the mobility of the perfect dislocation 1/3 <11-20> in the (0001) basal and prismatic (10-10) slip planes of the hexagonal structure. The dislocations are located in crystal (1) of a bicrystal among Zn, Be, Co, Hf, Ti, Zr, Cd, Y, Mg and Tl which are elastically anisotrope metals. They are parallel to the interface plane and are in elastic interaction with this interface and situated at a distance d therefrom. Each dislocation is characterized by its line direction and Burgers vector b. The interface is defined by its plane which is basal one for the two crystals and a null disorientation. The setting of the dislocation movement under the effect of the image force depends on the intensity of the elastic energy interaction of dislocation with interphase boundary and of the distance d where the dislocation is located.
The setting in motion is effective if the intensity of the image force (Fi = - E / d, E is the elastic interaction energy) is greater than the Peierls constraint. The dislocation is attracted or repelled upon the direction of image force. A critical distance, dc, is defined when image force is equal to the Peierls force. The dislocation is attracted to the interface when the crystal (2) is softer than the crystal (1), it is repelled when the crystal (2) is the hardest. The efficiency distance of image force increases with the absolute value of the difference in shear modulus of the materials constituting the bicrystal.
The favored slip plane is selected by the c/a ratio of the crystal which is located dislocation.
The result is in accordance with those of the behavior of dislocations in single crystals except for the cases crystals of the c/a ratio close to (8/3) (Mg and Co).Diplôme : Doctorat en sciences En ligne : ../theses/physique/AYA6802.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=10055 Interaction elastique dislocation-interface dans des aux bicristaux elastiquement anisotropes de structure hexagonale [texte imprimé] / Aicha Ayadi, Auteur ; Omar Khalfallah, Directeur de thèse . - جامعة الإخوة منتوري قسنطينة, 2015 . - 167 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
PhysiqueTags : Interface Dislocation Force image Contrainte de Peierls système de glissement structure
hexagonale élasticité anisotrope Dislocations Image Force Peierls stress slip system hexagonal structure elastic anisotropy
إنخلاع مستوى الانزلاق بنية سداسية قوة الصورة طاقة التفاعل المرن إجهاد Peierls تباين الخواص المرونيةIndex. décimale : 530 Physique Résumé : The movement of a dislocation in interaction with an interface, in the absence of external
stresses, is controlled by the balance of internal stresses. This assessment includes the friction force in the Peierls-Nabarro network stress and a force due to the anisotropy of the material called image force. We study the mobility of the perfect dislocation 1/3 <11-20> in the (0001) basal and prismatic (10-10) slip planes of the hexagonal structure. The dislocations are located in crystal (1) of a bicrystal among Zn, Be, Co, Hf, Ti, Zr, Cd, Y, Mg and Tl which are elastically anisotrope metals. They are parallel to the interface plane and are in elastic interaction with this interface and situated at a distance d therefrom. Each dislocation is characterized by its line direction and Burgers vector b. The interface is defined by its plane which is basal one for the two crystals and a null disorientation. The setting of the dislocation movement under the effect of the image force depends on the intensity of the elastic energy interaction of dislocation with interphase boundary and of the distance d where the dislocation is located.
The setting in motion is effective if the intensity of the image force (Fi = - E / d, E is the elastic interaction energy) is greater than the Peierls constraint. The dislocation is attracted or repelled upon the direction of image force. A critical distance, dc, is defined when image force is equal to the Peierls force. The dislocation is attracted to the interface when the crystal (2) is softer than the crystal (1), it is repelled when the crystal (2) is the hardest. The efficiency distance of image force increases with the absolute value of the difference in shear modulus of the materials constituting the bicrystal.
The favored slip plane is selected by the c/a ratio of the crystal which is located dislocation.
The result is in accordance with those of the behavior of dislocations in single crystals except for the cases crystals of the c/a ratio close to (8/3) (Mg and Co).Diplôme : Doctorat en sciences En ligne : ../theses/physique/AYA6802.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=10055 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité AYA/6802 AYA/6802 Thèse Bibliothèque principale Thèses Disponible
Titre : Caractérisation et analyse des cellules solaires à base de silicium multicristallin Type de document : texte imprimé Auteurs : Zohra Benmohamed ; Univ. de Constantine, Éditeur scientifique ; Mohamed Remram, Directeur de thèse Année de publication : 2009 Importance : 95 f. Format : 30 cm Note générale : 01 Disponible à la salle de recherche 02 Disponibles au magazin de la B.U.C. 01 CD Langues : Français (fre) Catégories : Français - Anglais
ElectroniqueTags : Caractérisation Analyse Cellules solaires Silicium multicristallin Impurities Dislocations Multicrystalline silicon Solar cells Efficiency
الشوائب العيوب البنيوية السليسيوم متعدد البلوراتالخلايا الشمسية المردودIndex. décimale : 621 Electronique Résumé : An understanding of the comportment of defects and Impurities in multicrystalline silicon in turn leads
to a clearer picture of the limiting mechanisms in solar cells made with this promising material, and points to
possible paths for improvement. In this study a three diagnostic approach has been adopted for the
characterization of multicrystalline silicon samples, it comprises structural, chemical and electrical analysis of
the various minority diffusion length limiting defects and impurities which are responsible for the degradation of
the performances of multicrystalline silicon solar cells.
Preferential defect etching ions provided for the structural analysis. This approach was useful in
determining the nature and distribution of the structural defects. The work then focuses on chemical
characterization of impurities and the analytical tool used for this purpose were Fourier Transform Infra-red
Spectroscopy (FTIR). The results of annealing processes shown that, Rapid Thermal Annealing can dissociate
some oxygen precipitates existing in silicon material. This dissociation is accompanied by a degradation of the
bulk diffusion length. The effect of RTA on oxygen precipitation is extensively depending on the thermal history
of the material, the initial oxygen content and the existing precipitates in the material.
The above characterization tools were well complemented by electrical characterization through
Surface photovoltage (SPV) to determined minority diffusion length.
The results of PC1D modelling on multicrystalline silicon solar cells revealed that dislocations are not
the major factor that influences electrical properties of material. Impurities which were already present in the
grown material in an inactive form in particular the growth of oxygen precipitates and metallic impurities and
which have been electrically activated in an inhomogeneous distribution are also a principal source of
deterioration of polycrystalline silicon solar cells performances.
Thus there is a scope for attaining still higher efficiencies by further optimization of growth material
and cell processes to reduce reflection loss and effectively trapping the light inside the cell.Diplôme : Doctorat en sciences En ligne : ../theses/electronique/BEN5287.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=2774 Caractérisation et analyse des cellules solaires à base de silicium multicristallin [texte imprimé] / Zohra Benmohamed ; Univ. de Constantine, Éditeur scientifique ; Mohamed Remram, Directeur de thèse . - 2009 . - 95 f. ; 30 cm.
01 Disponible à la salle de recherche 02 Disponibles au magazin de la B.U.C. 01 CD
Langues : Français (fre)
Catégories : Français - Anglais
ElectroniqueTags : Caractérisation Analyse Cellules solaires Silicium multicristallin Impurities Dislocations Multicrystalline silicon Solar cells Efficiency
الشوائب العيوب البنيوية السليسيوم متعدد البلوراتالخلايا الشمسية المردودIndex. décimale : 621 Electronique Résumé : An understanding of the comportment of defects and Impurities in multicrystalline silicon in turn leads
to a clearer picture of the limiting mechanisms in solar cells made with this promising material, and points to
possible paths for improvement. In this study a three diagnostic approach has been adopted for the
characterization of multicrystalline silicon samples, it comprises structural, chemical and electrical analysis of
the various minority diffusion length limiting defects and impurities which are responsible for the degradation of
the performances of multicrystalline silicon solar cells.
Preferential defect etching ions provided for the structural analysis. This approach was useful in
determining the nature and distribution of the structural defects. The work then focuses on chemical
characterization of impurities and the analytical tool used for this purpose were Fourier Transform Infra-red
Spectroscopy (FTIR). The results of annealing processes shown that, Rapid Thermal Annealing can dissociate
some oxygen precipitates existing in silicon material. This dissociation is accompanied by a degradation of the
bulk diffusion length. The effect of RTA on oxygen precipitation is extensively depending on the thermal history
of the material, the initial oxygen content and the existing precipitates in the material.
The above characterization tools were well complemented by electrical characterization through
Surface photovoltage (SPV) to determined minority diffusion length.
The results of PC1D modelling on multicrystalline silicon solar cells revealed that dislocations are not
the major factor that influences electrical properties of material. Impurities which were already present in the
grown material in an inactive form in particular the growth of oxygen precipitates and metallic impurities and
which have been electrically activated in an inhomogeneous distribution are also a principal source of
deterioration of polycrystalline silicon solar cells performances.
Thus there is a scope for attaining still higher efficiencies by further optimization of growth material
and cell processes to reduce reflection loss and effectively trapping the light inside the cell.Diplôme : Doctorat en sciences En ligne : ../theses/electronique/BEN5287.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=2774 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité BEN/5287 BEN/5287 Thèse Bibliothèque principale Thèses Disponible
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